TR&D2:BrainStructureandFunction P.I: John Detre, MD Co-Investigators: Brian Avants, PhD and Ze Wang, PhD ABSTRACT TRD2 focuses on neuroimaging methods for use in basic and clinical neuroscience. Much of this work concerns the development and application of arterial spin labeled (ASL) perfusion MRI, a method initiated by our Regional Resource (1). ASL provides noninvasive quantification of tissue perfusion (blood flow). In brain, cerebral blood flow (CBF) quantifies cerebrovascular function, but CBF also serves as a means of quantifying neural function more generally through the tight coupling between CBF and regional neural activity (2, 3). Over the past project period, TRD2 further developed ASL MRI technologies and applications at 3T and at 7T. Additional neuroimaging technology developed by TRD2 included imaging of myelin and myelin water, susceptibility weighted imaging, and the development of new signal-processing strategies for both functional and structural MRI of the brain. TRD2 also collaborated with TRD1 on metabolic imaging of the brain and with TRD4 on optical monitoring of CBF and metabolism in the brain. In the upcoming grant period, we plan to continue these lines of inquiry, and to collaborate with TRD3 on short-TE imaging.